Lubricating and cooling system for internal-combustion engines



E. J. HALL Feb. 15, 1927;

LUBRICATING AND COOLING SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed May 15, 1922 I 'iZIL'IIIIIt C' Inventor E'lbert Illa/ll flitorne grs I IIII Il I ll |"|'u| In I 1 I I I I "HlllllllllllllllllllllllllIIIIIIIIIIIIIIIHI I Patented Feb. 15, 1927'.

ELBERT J. HALL, OF BERKELEY, CALIFORNIA.

Application filed May 13,

This invention relates to a lubricating and cooling system for internal combustion d ll engines.

The invention conten'lplates both a method and an apparatus, and has for its object to simplify and improve the cooling and lubrication of an engine by utilizing a single medium for this purpose. This I accomplish by placing thecooling jackets in communication with the crank case of the engine and circulating oil or similar lubricant through such jackets and crank case and around the hearings to be lubricated. Preferably, a pump is placed in the crank case and the oil is pumped through the cooling jackets and returned either directly to the crank case or throu h a cooling radiator. The walls ofthe coo ing jackets and crank case are provided with cooling fins and a fan is used to direct a blast of air thereon and assist in cooling. Oil being a good conductor of heat will quickly transmit the heat from the cylinders to the cooling fins.

Aside from the obvious advantage of simplification, the present invention is of decided advantage when used in connection with sleeve cylinders. Usually the sleeve cylinders are fitted in an aluminum block, and, owing to the unequal expansion between aluminum and cast iron, there is bound to be a leakage from the cooling jackets into the crank case. Where water is used for cooling, some of this-water will find its way into the crank case and interfere with the proper lubrication of the engine. This has been found to be one of the chief objections to the use of sleeve cylinders. Obviously, where oil is used both for lubricating and cooling, such leakage ofiers no objection. Moreover, if an aluminum block be used, it will assist materially in conducting heat away from the oil, making it unnecessary in many cases to pass the oil through a cooling radiator. v

In the accompanying drawing-- Fig. 1 shows a vertical central sectional view of an internal combustion engine embodying In invention.

Fig. 2 s owe a transverse sectional view of the same.

Fig. 3 shows a modified arrangement wherein a radiator is interposed between the cooling jackets and the crank case.

The motor herein illustrated comprises the usual cylinder block 10, crank case Ill and 1922. Serial No. 560,788.

cylinder head assembly 12. The cylinder head assembly has a cooling jacket 13 and the cylinder block is likewise jacketed, as shown at 14. These cooling chambers are 111 open communication with each other and from the cooling jacket in the cylinder block passageways 15 extend down to the crank shaft bearings 16 for lubricating the latter. @pening JIItO the cylinder head assembly at the desired height is an overflow pipe 17,

which extends down into the crank case for returning the oil to the latter. Within the crank case is a pump 18, preferably of the centrifugal type, discharging into a conduit 19, which leads up engine to the cooling jacket 13. The pump 13 operated in any of the usual ways, as by gearing 20 connected with the crank shaft 21 of the engine. Preferably, the pump is provided with a foot valve 22 to prevent oil from flowing back when the pump is stopped.

@il in the crank case is thus pumped up to the cooling jackets, where it serves to cool the walls of the cylinders, and upon reaching the level of the overflow pipe 17, it is returned to the crank case. It is contemplated to fit the cylinder head, cylinder block and crank case with cooling fins 22 whereby to radiate heat from the walls. If the cylinder block or other partsbe made of aluminum or alloy, such material will serve ideally as a conductor of heat. A fan 23 is provided for the purpose of directing a blast of air across the cooling fins to assist in the cooling thereof.

A modification is shown in Fig. 3, which is intended for larger engines. In this instance, T preferably make use of a cooling radiator 24 which is connected by a pipe 25 at its upper end to the jacket of the cylinder head assembly and at its lower end is connected by a pipe 26 to the crank case. A pump 27 is interposed in the pipe 26 to control the discharge of oil from the radiator into the crank case. This pump .may be driven in any preferred way from the engine. Tn smaller types of engines it may not be necessary to employ the cooling radiator, the fan alone being suiiicient.

In certain types of engines the oil in the cylinder head assembly may also serve to lubricate the bearings of a cam shaft 28. Also where a transmission housing 29 is formed integrally with the crank case a along one side of the transmission or clutch mechanism within can be lubricated from the oil in the crank case. shown as being provided with cooling fins 31. If desired, the driving means for the fan, indicated at 32, may be so enclosed as to receive its lubrication from the crank case. This is done by providing a dam 33 at the front of the cylinder head assembly, which permits oil in the jacket to overflow on to the fan-driving means.

Oil as a cooling agent has the advantage of being a good conductor of heat and it also is non-freezing. Inasmuch as only one medium is used for both cooling and lubricating purposes, a single filling of the supply tank or radiator will take the place of the separate fillings heretofore required; Certain mixtures of oil and other ingredients can readily be produced which will give a satisfactory ethciency both for luburicating and cooling. If the cylinder block or other parts be made of aluminum or alloy, such material will serve ideally as a conductor of heat and the leakage which unavoidably occurs between the block and the sleeve cylinder will not present the objections arising I where water is used as a cooling medium.

engine is not running.

Many other advantages will be apparent to those skilled in the art. Various changes in the construction and operation of the apparatus herein shown and in the manner of applying my invention may be employed This transmission housing is I without departing from the spirit of the same as disclosed in the appended claims.

Having thus described my invention, what I claim and desire to secure byLetters Patent 1s:

1. In an internal combustion engine, acylinder, a cooling jacket for the side walls and head of the cylinder, a crank case, a pump for supplying oil from the crank case to the cooling jacket, and an overflow return pipe for the oil extending from a point above the cylinder head to the crank case, whereby a body of oil is maintained around the walls of the cylinder and above its head and the heated oil is drawn off from the highest level and returned to the crank case for cooling, said cooling jacket and crank case being formed of aluminum and fitted with radiating pins to assist in cooling the oil.

2. In an internalcombustion engine of the character described, a plurality of cylinders,

a jacket surrounding the cylinders, a crank case with an oil'sump formed therein, a pump in the sump adapted to elevate the oil and to circulate it through the cylinders, a head closing the upper ends of the cylinders, a cover enclosing the heads and forming a cooling chamber above the heads, a cam shaft extending through said cover and cooling chamber, valve stems arranged in the cover and extending through guides in the cylinder head, said cylinder jackets having ports formed therein through which the oil is adapted to discharge upwardly into the cooling chamber above the cylinder heads, and an overflow pipe forming a connection between the cooling chamber and the crank case to permit re-circulation of the oil, the

upper end of said overflow pipe extending up into the cooling chamber to a point above the cam shaft to permit continuous submersion of the cam shaft and valve stem guides.

ELBERT J. HALL. 

